Mobile computing devices may use a wide variety of input methods. In addition to buttons and other physical input devices, mobile computing devices typically include an electronic display capable of detecting the presence and location of the touch within the display area (i.e., a “touchscreen”). Numerous software applications for mobile computing devices make use of touchscreen inputs, and thus touchscreens have dramatically expanded the type and range of possible user interactions with mobile computing devices.
However, touchscreen interactions require the user's focused attention to see a target to touch (e.g., an icon, text, etc.) or a response to the input. Further, more complex software applications may be difficult or cumbersome to control through interactions with a touchscreen. Moreover, many interactions with mobile computing devices require one hand to hold the mobile computing device so that fingers of the other hand may interact with the touchscreen. Such interactions may be difficult or impossible in certain situations, such as when the mobile computing device is in a bag, pocket or case.